A method and apparatus for burn-in of semiconductor devices is disclosed. A semiconductor device that includes built-in self test circuitry is coupled to a socket on a burn-in board. The burn in board and the semiconductor device are heated. Burn-in instructions can be transmitted to the semiconductor device through a JTAG terminal of the semiconductor device. Upon receiving a burn-in instruction through a JTAG terminal, the built-in self test circuitry is operable to perform one or more burn-in function. This allows for burn-in of a semiconductor device without any transfer of data through the data input terminals of the semiconductor device.